Can Antidepressants alter the personality?

December 14th, 2009

A recent article featured in The Guardian has exposed fears that taking antidepressants may change aspects of a persons personality.

The personality traits we inherit from our parents often have a huge bearing on our chances of becoming depressed. Neuroticism means that a person has a strong tendency towards negative emotions and emotional instability and scientists believe that this is one of the main links to depression.

Selective serotonin-reuptake inhibitors (SSRIs) are used to treat depression by boosting the amount of a chemical called serotonin in your brain. Doctors previously thought that SSRIs boosted mood by increasing levels of serotonin in people whose levels were depleted. People who have used the medication reported positive effects such as feeling more sociable, less emotional and an improvement in mood but upon reflection, doctors have said these side effects could be a result of changed personality.

The new study to investigate the matter further looked at how both personality traits and depression changed in three groups of patients. The first groups received the antidepressant parotoxtine, another took placebo pills, and the third received cognitive therapy.

Those who were treated with the antidepressant or cognitive therapy showed great improvement and reported feeling less depressed, less neurotic, and more extroverted. Those who took the dummy placebo pill were also less depressed but saw little change in their personality scores for being neurotic or extrovert.

A standard measurement for personality traits and depression was used to gage the effect of each treatment. Researchers found that changes in personality for people treated with parotoxtine were much greater than the change in depression alone. Those who received cognitive therapy did experience change but the difference could be attributed to improvements in depression.

Lastly, those taking the antidepressant showed the biggest decrease in neuroticism during the study and were the least likely to become depressed again during the following year.